{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,23]],"date-time":"2025-10-23T05:38:45Z","timestamp":1761197925105,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,2,27]],"date-time":"2021-02-27T00:00:00Z","timestamp":1614384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In the present paper, we examine the quantum entanglement for more general states of two-qubit system in the context of spin coherent states (SCSs). We consider the concurrence as a quantifier of entanglement and express it in terms of SCSs. We determine new set of maximally entangled conditions that provide the maximal amount of entanglement for certain values of the amplitudes of SCSs for the case of pure states. Finally, we examine the entanglement of a class of mixed states of the two qubits and provide the range in which the entanglement value is maximal with respect to the values of the amplitudes of SCSs.<\/jats:p>","DOI":"10.3390\/sym13030386","type":"journal-article","created":{"date-parts":[[2021,2,27]],"date-time":"2021-02-27T03:44:31Z","timestamp":1614397471000},"page":"386","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Entanglement of General Two-Qubit States in a Realistic Framework"],"prefix":"10.3390","volume":"13","author":[{"given":"Sayed","family":"Abdel-Khalek","sequence":"first","affiliation":[{"name":"Department of Mathematics and Statistics, College of Science, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kamal","family":"Berrada","sequence":"additional","affiliation":[{"name":"Physics Department, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 13318, Saudi Arabia"},{"name":"The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34151 Miramare-Trieste, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eied M.","family":"Khalil","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics, College of Science, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fadhel","family":"Almalki","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics, College of Science, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"807","DOI":"10.1007\/BF01491891","article-title":"Die gegenw\u00e4rtige Situation in der Quantenmechanik","volume":"23","year":"1935","journal-title":"Naturwissenschafen"},{"key":"ref_2","unstructured":"Nielsen, M.A., and Chuang, I.L. (2000). 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